The present invention relates to a method and device for removing gas from gas containing blood by operation of a centrifuging device.
This type of device is disclosed in British A-2 063 108. Further devices for separating gas from gas containing blood are described in U.S. Pat. Nos. 3,785,380, 4,368,118, 4,388,922 and 5,451,321, as well as in German DE-C-36 24 363 and 36 41 644 and DE-A-43 29 385.
Blood given to a patient should not contain any air or other gas, even in the form of micro-small bubbles of gas. The blood is fed to the patient by a pressure pump. Although that is the preferred field of use of the invention, it does not exclude the invention also being used to remove air from blood which is drawn from a patient at the site of a wound, since it frequently cannot be avoided that air is also drawn into the bloodstream at the site of the wound. The air must be removed from the blood as rapidly as possible and as close as possible to the wound since it can otherwise damage the blood. Other possible fields of use of the invention are the removal of gas from gas-containing blood which is transported from one instrument to another or to a container.
The object of the invention is to improve the efficiency of the gas removal and, in particular, to provide a method and a device with which even micro-small bubbles of gas can be removed from gas containing blood, even if the gas containing blood is being conveyed in a large volume per unit of time.
The invention concerns a method and device for removing gas from gas containing blood. A non-rotating cyclone eddy chamber has the blood circulating therein and centrifugal force separates the blood radially outward and the gas radially inward. The cyclone inlet comprises a blood inlet channel that extends in a helical circular form developed to narrow in funnel like manner in the direction of flow toward the cyclone eddy chamber to accelerate the blood flow entering that chamber tangentially. A gas outlet is arranged in the radially inner center of the cyclone eddy chamber path while the blood outlet is coaxial and outward of the gas outlet.
Other objects, features and advantages of the present invention will become apparent from the following description of the invention which refers to the accompanying drawing.